What is the primary function of antibodies?

The primary function of antibodies is to bind to antigens and mark them for elimination. Antibodies are specialized proteins produced by B cells of the immune system in response to foreign substances, known as antigens, which can include pathogens like bacteria and viruses. Once an antibody binds to an antigen, it marks it for destruction or neutralization by other immune cells. This process is critical for the adaptive immune response, allowing the body to specifically target and eliminate pathogens while also helping to remember the antigens for a faster response if encountered again in the future.

Antibodies do play a role in neutralizing toxins, but their central function is more about marking and aiding in the removal of antigens rather than solely neutralization. Transporting oxygen in the blood is the role of hemoglobin, not antibodies. Similarly, hormone production for metabolic processes involves different specialized cells and molecules, not antibodies. Therefore, binding to antigens for elimination encompasses the essential action of antibodies within the immune system.